Complete recovery of M. luteus could not be achieved in these experiments, which is not surprising. However, the robotic sampling operation could achieve
much better recovery of M. luteus than could manual sampling. This better result could be attributed to the robot's more precise control over sampling speed,
pressure, and area (5) (see Figures 3–7).
The experimental data suggest that the operating parameters of robotic surface sampling shown in Figure 7 result in the best
rates of recovery. However, further investigation will be required to determine whether higher recovery rates can be obtained
with other robotic sampling parameters. The authors will investigate both the influence of robotic sampling parameters as
well as other variables such as swab-tip composition, flexibility of the swab's rod, and recovery media. It is significant
that the recovery rates observed with the robotic swab method were in many cases three to fourfold higher than those that
resulted from manual swabbing under otherwise identical experimental conditions. These results indicate that robotic sampling
has the potential to improve the limit of detection of surface monitoring and also to reduce variability.
The authors believe the automated approach to monitoring reduces the likelihood of false-positive results, although they did
not attempt to quantify this benefit. Of course, because the robotic sampling parameters are variable and user-selectable,
it will be possible for users to define sampling conditions that are optimal for their particular application (6). The authors
are also aware that the robotic surface-sampling method may afford advantages in terms of chemical recovery. This means that
a robot installed in an isolator for microbiological sampling could be used to assess cleaning effectiveness as well. This,
of course, would depend upon the location of the robot within an enclosure or RABS environment.
Mayumi Maruyama, Tomoo Matsuoka, and Motonari Deguchi work in the Microbial Control Department at Shibuya Kogyo Co., Ltd. in Kanazawa, Japan. James E. Akers* is the president of Akers Kennedy & Associates, PO Box 22562, Kansas City, MO 64113, firstname.lastname@example.org
*To whom all correspondence should be addressed.
1. J.E. Akers and Y. Oshima, "PAsepT, Aseptic Vial Filling Processing Based on Principles of PAT," in Presentation at the ISPE Annual Conference (San Antonio, TX, 2004).
2. M. Deguchi, et al, "Development of an Advanced High Speed Aseptic Filling System," in Proceedings of the PDA International Congress, (Kyoto, Japan, 2001).
3. B. Ljungvist, B. Reinmüller, and R. Nydahl, "Microbiological Assessment in Clean Rooms for Aseptic Processing," J. R3 Nordic 23(3), 7-10, 1995.
4. J.E. Akers, "Environmental Monitoring and Control: Proposed Standards, Current Practices and Future Directions," J. Pharm Sci. Techn. 51(1), 36-47, 1996.
5. NASA, NASA Handbook for Biological Engineers (National Aeronautics and Space Administration, Washington, DC, 1971).
6. J. Levchuk, "FDA's Perspectives on Aseptic Process Validation," in Proceedings of the Third Annual GMP by the Sea Conference (University of Rhode Island School of Pharmacy, Kingston, RI, 2003).